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Camry 1996 V6 LE
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Discussion Starter #1
Morons at Hayttsville, MD emission test station do not know that Camry 95 V6 is OBD-II and even didn't want to hear anything about it: "we do not use obd2 on vehicles older than 96".... Monkeys. :headbang:
Anyway, tested with that stupid crap in the tail pipe. HC at idle is high: 220 vs allowed 175. Most of the parts which could be blamed are either new or cleaned:
1) brand new catalytic
2) new spark plugs
3) new PCV
4) cleaned EGR (valve, modulator and both EGR pipes) (no codes! a month ago fixed P0401).
5) new all 3 O2-sensors.
6) cleaned IAC, throttle body, air intake, new air filter, fuel filter
7) I drove about 30 miles before going to test
8) gas is 93 octane.

What else it could be? How can I diagnose too rich or too lean mixture using OBD-II? Where to look?

Actually, one potential mistake I made: my catalytic monitor is not marked as "Completed" yet (need to perform that driving pattern). But I'm not sure it matters since those idiots did not read OBD-II at all....
 

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Do a fresh oil change. High HC with all new exhaust, clean EGR, new PCV, and no MIL codes can only mean dirty oil, hence higher HC.

Use 5w30 Valvoline/Shell/Esso non-synthetic.

Rev up to 2500 (or go on highway with O/D off for 10 mins) and have at least 1/4 tank of gas.

Failing all that 1L of methanol to gas tank will pass you.
 

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抵抗は無駄で&#
2002 Solara SLE V6
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9,085 Posts
drive on highway at 45-55mph for 15 mins then take an exit and do local driving (you cannot shut off the engine in meantime) at no faster than 20-30mph for another 15 mins (traffic lights do not matter) and cat test will get completed.

what are your fuel trims at while idling and at 2.5k rpm rev?

high HC ... hmmmm, make sure that cat converter test gets marked completed first.
what were the other 2 emission numbers, CO and NOx ?
 

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2000 Solara
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252 Posts
if you have to take the roller test, over-inflate your tires(40psi), remove your power steering belt, change the oil and take the test - it doesn't buy you alot, but maybe just enough to pass.

and, yes, you have make sure the cat is "ready"

Keep us posted!
 

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Camry 1996 V6 LE
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1,128 Posts
Discussion Starter #6 (Edited)
I'll try another station in more educated area than getto in Hayttsville, but not sure they will use OBD2 still....
Oil is 2000 miles old, not synthetic.
In MD they don't use roller, just idling and holding 2,500 rpms for some time.
And I DID drive for 30 minutes on a highway before going there....
I'll make the cat monitor "completed" first before going to re-test.
As to other numbers - there not many of them:
====
CO% - 0.15 (allowed 1.00)
Catalytic converter: PASS (no numbers, just word "PASS")
Gas cap: PASS
CO + CO2%: 15.34 (minimum is 6%; if less - means leak somewhere, not enough flow)
====
There is no NOx number in the report.

So, cat they claimed as "PASS".
Can Seafoam help to lower hydrocarbons, btw?


And I'll check fuel trims with OBD-II at 2500. What should I see, actually? (I need to re-read that topic of 73sports, probably...)
 

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Turbo Snail
Cam A Roo
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5,300 Posts
yeah seafoam should help with HC, just make sure to follow the directions :)

6oz in intake, holding rev 500-1000 over normal idle, once 6oz is in car idle back down to normal idle, shut off for 5 minutes. After 5 minutes, restart and drive aggressively.

Excessive HC's are due to unburned fuel molecules. This can be caused by, but not limited to, problems with the ignition system (plugs, wires, timing, etc.), air/fuel mixture or fuel delivery (ie vacuum leaks), slow reacting oxygen sensor, diluted engine oil, or a dirty air cleaner.

What oxygen sensors did you replace the ones in the car with?

and my 95 is I4 with obd-II also :)
 

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抵抗は無駄で&#
2002 Solara SLE V6
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9,085 Posts
I would try changing oil to fresh one (2k miles on dino is nowhere near fresh) too as suggested above.

fuel trims at normal idle should be around +/-5% on Long Trim while Short Trim should say zero (at warmed up engine).
I think fuel trims at 2.5k rpms should be more around zeroes than at idle (depending on what former reading was).

wondering how they come up with passed cat test without plugging into the obd2 connector, hmmm, strange... and why no NOx in report?

sea foam might help remove that carbon buildup, so it may have some effect on emissions as well.

IIRC HC refers rather to an unburned fuel, so look for any signs of running rich in obd2 (negative fuel trims, rich readings on upstream oxygen sensors, etc.)

there is one more ghetto method for passing emissions, but that requires mixing some acetone with gasoline (don't remember ratio) and filling the tank with it.

either way keep us posted :)
 

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1MZ powered MR2
1991 MR2
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OEM or aftermarket cat? I have the same issue, but I have an aftermarket cat. The factory cat seems to eat up the HCs a bit better.
 

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Camry 1996 V6 LE
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Discussion Starter #10
Excessive HC's are due to unburned fuel molecules. This can be caused by, but not limited to, problems with the ignition system (plugs, wires, timing, etc.), air/fuel mixture or fuel delivery (ie vacuum leaks), slow reacting oxygen sensor, diluted engine oil, or a dirty air cleaner.

What oxygen sensors did you replace the ones in the car with?
Timing belt is new, spark plugs are all new (OEM double electrode (NGK blablaTR11 platinum). No wires on 95 V6 (coils are on every spark plugs, all coils were tested (anyway, no P030x codes)). Vacuum leak.... Again, no codes, but I understand that vacuum leak may exist w/o code.... Will check OBD-II data and will try to figure out potential problem. Air filter is new as well.
O2 sensors were replaced by universal Denso ones (OEM, but w/o connector).
 

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I don't recommend Seafoam, it's a mixture of naptha oil, rubbing alcohol, and mineral spirits basically.

Toyota Combustion Cleaner, Mopar Combustion Chamber cleaner, or GM Top End cleaner are far superior in detergent properties, factory approved, and cost less.

As with all cool things, not available in California however.
 

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Camry 1996 V6 LE
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1,128 Posts
Discussion Starter #13
Will give that Mopar CCC (or other two, depending which one I find) a try. Also planned to do Auto-RX. So, sounds like a plan:
1) Check fuel trims by monitoring OBD-II
2) Make catalytic monitor "complete".
3) Auto-Rx
4) Combustion cleaner
5) Change oil
6) Use 91 - 93 octane fuel (I am doing it already anyway)
7) Go another station, drive at least 20 min before.

Did anybody try this: http://www.autobarn.net/ch05063.html
 

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抵抗は無駄で&#
2002 Solara SLE V6
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9,085 Posts
Will give that Mopar CCC (or other two, depending which one I find) a try. Also planned to do Auto-RX. So, sounds like a plan:
1) Check fuel trims by monitoring OBD-II
2) Make catalytic monitor "complete".
3) Auto-Rx
4) Combustion cleaner
5) Change oil
6) Use 91 - 93 octane fuel (I am doing it already anyway)
7) Go another station, drive at least 20 min before.

Did anybody try this:
http://www.autobarn.net/ch05063.html
That CRC additive/cleaner might be worth trying. It looks something like new thing on the market? anyways CRC is a good chemical company, might be worth trying.

some customer reviews on amazon:
 

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抵抗は無駄で&#
2002 Solara SLE V6
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9,085 Posts
also check the PCV valve, grommet and hoses, high HC levels may be coming from there.

other than that high HC levels might be related to Catalytic converter efficiency or EVAP (evaporated HC). since you have no trouble codes I would rather leave EVAP alone, it's very sensitive, so probably nothing wrong with it.
 

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Turbo Snail
Cam A Roo
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5,300 Posts
Timing belt is new, spark plugs are all new (OEM double electrode (NGK blablaTR11 platinum). No wires on 95 V6 (coils are on every spark plugs, all coils were tested (anyway, no P030x codes)). Vacuum leak.... Again, no codes, but I understand that vacuum leak may exist w/o code.... Will check OBD-II data and will try to figure out potential problem. Air filter is new as well.
O2 sensors were replaced by universal Denso ones (OEM, but w/o connector).

If the O2 sensors were the ones you "Wire" together, I would look on getting some direct replacement ones ... Or look into getting the vehicle hooked up to an OBDII Scanner with datastream and monitor the upstream and downstream sensors. I have a suspicion that your O2's aren't working efficiently, causing your car to run more lean
 

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Camry 1996 V6 LE
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Discussion Starter #18
If the O2 sensors were the ones you "Wire" together, I would look on getting some direct replacement ones ...
Those Denso sensors are EXACTLY the same as the "direct replacement", the only diff is in missing connector.

Or look into getting the vehicle hooked up to an OBDII Scanner with datastream and monitor the upstream and downstream sensors. I have a suspicion that your O2's aren't working efficiently, causing your car to run more lean
I'll have a look but O2-sensor monitoring marked as "complete".
 

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Turbo Snail
Cam A Roo
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Those Denso sensors are EXACTLY the same as the "direct replacement", the only diff is in missing connector.



I'll have a look but O2-sensor monitoring marked as "complete".
I've seen direct replacements with no connector not work correctly due to poor wiring

How did you connect it to the plug? Did you solder it or do Pin-Out removal and connect pins to it?
 

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Camry 1996 V6 LE
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Discussion Starter #20
Soldered. It is all good, trust me. In the case of bad contact I'll either would get MIL or O2 monitor would never be "complete".
 
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